The primary objective of the research program continues to be a clarification of the role of behavioral and environment factors in the pathogenesis of cardiovascular disease. To this end, investigations continue to focus upon the experimental analysis of relationships between cardiovascular functions and controlled behavioral interactions in laboratory carnivores and primates. Methods for intermittent and continuous monitoring of peripheral blood pressure, heart rate, respiratory rate, O2 consumption, coronary inflow, aortic flow, both right atrium and aortic pressures, renal pressure, as well as pulmonary and regional flows and pressures are applied under conditions of controlled environmental stimulation and behavioral stress. Integrated measures of simultaneous and sequential interactions are presently being obtained, and the pre-processing and interfacing of physiological recordings for computer analysis provide an online printout of all monitored circulatory functions. Operant and respondent conditioning techniques continue to be used to establish and maintain both simple and complex behavioral repertoires in baboons, monkeys, and dogs involving laboratory paradigms of anticipation, discrimination, escape, avoidance, and conditioned suppression. Concurrent measurements of the circulation and behavior provide a basis for assessing the selective role of classical physiological mechanisms in the initiation, regulation, and maintenance of cardiovascular responses to environmental interactions with the intact, unanesthetized animal. In addition, functional relationships between circulatory reactions and behavior are further investigated in instrumental conditioning experiments in which significant environmental consequences are made contingent upon selected cardiovascular responses. Controlled pharmacological and surgical manipulations are experimentally evaluated againt such baseline observations to extend knowledge of cardiovascular physiology and pharmacology in relationship to medically important, but otherwise inaccessible, behavioral interactions.